THIS PROCEDURE SHOULD BE PERFORMED UNDER THE DIRECTION OF AN
HISTORICAL ARCHITECT OR ENGINEER TO DETERMINE THE MOST EFFICIENT
AND LEAST DESTRUCTIVE MANNER FOR EXECUTING THE WORK. APPROVAL
FROM
THE REGIONAL HISTORIC PRESERVATION OFFICER IS REQUIRED.

PART 1---GENERAL

1.01 SUMMARY

A. This procedure includes guidance on removing and
replacing deteriorated stone masonry.
It should be used
in conjunction with procedure 04520-02-R
"Repointing
Masonry Using Lime Mortar" and
04100-03-S "Preparing Lime
Mortars for Repointing Masonry".

B. Damage to stone in the form of cracking, splitting
and
spalling often occurs in areas sheltered
from direct
rain-washing.

C. See 01100-07-S for general project guidelines
to be
reviewed along with this procedure.
These guidelines
cover the following sections:

1. Safety Precautions

2. Historic Structures Precautions

3. Submittals

4. Quality Assurance

5. Delivery, Storage and Handling

6. Project/Site Conditions

7. Sequencing and Scheduling

8. General Protection (Surface
and Surrounding)

These guidelines should be reviewed
prior to performing
this procedure and should be followed,
when applicable,
along with recommendations from the
Regional Historic
Preservation Officer (RHPO).

1. Weather: Do not proceed
with patching or
replacement under adverse
weather conditions, or
when temperatures are
below or above manufacturer's
recommended limitations
for installation; Proceed
with the work only when
forecasted weather
conditions are favorable
for proper cure.

2. Wet Weather: Do not
apply or mix mortar on outside
surfaces with standing
water or outside during
rain.

3. Cold Weather, winter construction
is not allowed
without consent of Regional
Architect; Winter
construction (midwest
region) is defined as any
time between December
1 and March 1 and/or when
surface temperature of
masonry is below 40oF. or
air temperature is predicted
to be below 40oF.
within 48 hours; Heat
mortar materials to above
40oF. if necessary.

4. Hot Weather: The surface
temperature of the work,
not the ambient temperature,
should not be higher
than 100oF.; Mortar mixing
should be done only in
the shade; Cover mortar
in hot weather to reduce
evaporation; Pointing
work should be done in the
shade; Work around
the building during the day so
that the fresh work will
be shielded from direct
sunlight to reduce evaporation
rate.

5. All work must be suspended
during frosty weather
unless a heated enclosure
is provided. Work should
not be done in full sun
at temperatures above 27oC.
unless shading of the
walls is provided and the
masonry wall temperature
is kept below this point;
Burlap sacking and water
misting may be necessary
to control evaporation;
High temperatures can cause
flash setting of cements
and rapid evaporation of
water in the mix, leading
to lack of development of
final strength by the
cement.

6. Special Precautions and Notes:
Do not allow
masonry to freeze until
mortar is thoroughly dry
and hardening almost
complete (approx. three days
time); The setting of
lime mortar is very much
slower than that of cement
mortar because the
curing requires the absorption
of carbon dioxide to
form hard lime carbonates;
It is a very lengthy
process, so do not expect
it to become hard
immediately, especially
at the core of large masses
of masonry.

PART 2---PRODUCTS

2.01 MANUFACTURERS

A. Repointing Tools: Available from good hardware
stores,
building material suppliers or mail-order
catalogues.

4. Colored Mortar Pigment: Natural
and synthetic iron
oxides and chromium oxides,
compounded for use in
mortar mixes. Use
only pigments with record of
satisfactory performance
in masonry mortars.

5. Water: Clean, free of
oils, acids, alkalis and
organic matter.

6. Aggregate for Grout: ASTM
C404.

G. Manufactured and raw materials accessory to the
primary
products.

1. Supports, fasteners, installation
accessories, and
anchors: Stainless
steel only for use with
granite. Brass,
bronze, or stainless steel for use
with limestone and other
masonry.

2. Flashings or barriers: Sheet
copper or as
detailed.

2.03 EQUIPMENT

A. Trowels: range in length from 10-12 inches

B. Chisels: Joint chisels or a standard mason's
chisel with
a 1-1/2 in. blade and a long narrow
handle

C. Hammers:

1. 5# stone dressing hammer

2. 2# striking hammer

3. "No-Bounce" hammer

4. Full size and one half size
brick hammers

D. Joint Tools: (see 2.01 MANUFACTURERS above)

1. 3/8"-1/4" raised
beaded tool

2. 3/8"-1/4" beaded
striking tool

3. 1/2" raised beaded tool
with offset handle

4. 1/2" flat joint iron

5. Pointing tool should be about
1/16" narrower than
the joint being filled
to achieve good compaction

E. Hawks: Plywood or steel hawk (mortar board)

F. Brushes:

1. Natural bristle brushes

2. Stiff bristle brushes (no
wire)

G. Spray bottle

2.02 MIXES

A. Measurement and Mixing: Measure cementitious
and
aggregate material in a dry condition
by volume or
equivalent weight. Do not measure
by shovel, use known
measure. Mix materials in a clean
mechanical batch
mixer.

B. Consistently and accurately measure materials
for each
batch.

C. Mix for at least five minutes in a mechanical
batch mixer
or mortar box.

1. Mixer Pointing Mortar: Thoroughly
mix cementitious
and aggregate materials
together before adding any
water. Then mix
again adding only enough water to
produce a damp, unworkable
mix which will retain
its form when pressed
into a ball. Maintain mortar
in this dampened condition
for 1-to-2 hours. Add
remaining water in small
portions until mortar of
desired consistency is
reached. Use mortar within
30 minutes of final mixing;
do not retemper or use
partially hardened material.

E. Mix firm dry consistency for repointing.

F. Discard mortar not used within two hours after
mixing; do
not retemper at mixer.

G. Dispose of waste mortar and cleaning water in
approved
manner; do not contaminate the site,
adjoining property,
or waste to sewers.

H. Colored Mortar: Produce mortar of color
required by use
of selected ingredients. Do not
adjust proportions
without RHPO's approval.

1. Color Pigmented Mortar: Where
colored mortar
pigments are indicated,
do not exceed pigment-to-cement ratio of 1-to-10, by weight.

2. Match original color and texture
for each kind of
mortar and masonry work.

3. Match to inner mortar color
which has been
protected from weathering
and soiling, not face
color.

A. Surface Preparation: Where fresh masonry
joins existing
work, clean the exposed surface of the
set masonry by
removing loose stone and mortar and
wet lightly to obtain
the best possible bond with the new
work.

3.02 ERECTION/INSTALLATION/APPLICATION

A. Carefully remove by hand, as indicated, any stone
which
has deteriorated, shifted, or is damaged
beyond repair.

1. Carefully cut out perimeter
joints of stone by hand
using a hammer and chisel.

2. Break down the rest of the
damaged stone with
vertical saw cuts and
break it up with a hammer and
chisel.

B. Carefully clean out the cavity to receive the
stone.
Remove mortar, loose particles and other
debris from in
preparation for resetting.

C. Thoroughly wet the cavity with water; Dampen the
new or
salvaged stone with water.

D. Spread a 1/2 inch thick mortar bed into the open
cavity;
the new mortar should consist of coarse
sand and grit to
match the original mortar. Butter
vertical joints for
full width before setting and set unit(s)
in full bed of
mortar, unless otherwise indicated.

E. Repair and/or replace removed stone with salvaged
stone,
where possible, or with new stone to
match existing,
including size. Set the stone
in the cavity.

F. Fill the joints with a grout of lime and low sulphate
pozzolanic fly ash (PFA) or lime and
HTI powder.

G. Tool joints after setting to match joints of surrounding
stone.

H. Repoint new mortar joint to comply with requirements
for
repointing existing masonry, except
rake out joints
before mortar sets.

3.03 ADJUSTING/CLEANING

A. Wipe all excess mortar as the work progresses.
Dry brush
at the end of each day's work. After
mortar is
thoroughly set and cured, clean new
masonry surfaces,
walls, sills, overhangs, etc., of all
loose mortar, and
dirt and point up all nail holes, cracks,
etc., after
which wash down all masonry walls, leaving
them clean and
neat.